The Differences and Similiarities between Night Vision and Infrared Thermal Imaging Cameras
Today, night vision is a very common term used in countless action movies and frequently seen on the news in use by military and police forces. While it may seem like night vision should belong to the science fiction genre it is indeed a real part of everyday military and police search operations. Night vision can allow you to distinguish human forms at more than 200 yards. Night vision can be accomplished in one of several ways including image enhancement, laser illumination or infrared thermal imaging. The use of infrared light and night vision devices should not be confused with thermal imaging which creates images based on differences in surface temperature by detecting infrared radiation (heat) that emanates from objects and their surrounding environment
At Infrared Cameras Inc. we offer the typical green low light night vision cameras often seen on television or even showing up on some digital video cameras these days, but it is not our primary business. Our primary business are night vision cameras in the form of infrared thermal imaging cameras. This type of night vision camera can be much more useful for any type of night time or no light application. If you have seen the movie “Predator”, then you have seen how an infrared thermal camera works. By allowing the user to choose a variety of palettes and adjust the temperature level and span, infrared cameras make it far easier to distinguish human forms in the dark or anything that is emitting infrared radiation, which in fact is everything. Quantative thermal infrared cameras can measure temperature when set correctly and qualitative thermal cameras cannot. Both systems allow the viewer to quickly identify anything that will give off heat (such as animals) as opposed to the enhanced imaging green light that the typical night vision camera offers. These types of systems use image intensifiers. In other words they intensify visible light, moon light, starlight, etc.
The image enhancement techniques that are used in typical night vision devices work by amplifying any visible light. Infrared light sources can be used to augment the available ambient light for conversion by night vision cameras. Most of this visible light is barely noticeable by the human eye. This gives an image which allows the user to see through the dark by amplifying the existing light available. In true darkness night vision cameras become nearly useless unless they can rely on infrared light or utilize illuminators.
On the flip side infrared thermal imaging cameras see light in the infrared spectrum and sensors sensitive to heat (infrared radiation). This energy hits each pixel on the detector much like a CCD digital camera and convert the energy into an image. This literally allows the viewer to not only see through the dark, but through fog, smoke, rain, etc. This energy is emitted ( given off) by everything in the world above -459 F or -273 C. There is actually nothing that is this cold so infrared radiation is emitted by literally everything in the world and everything outside this world. Thermal imagers can quickly and easily identify any source of heat. This is what makes infrared thermal cameras different from and in some cases superior to your typical night vision camera. Thermal infrared cameras allow for a great overall image at night or in any low light situation, and are typically used for any application where measuring temperatures is required. Unlike night vision cameras, thermal infrared cameras will allow you to see in absolute darkness. As you can see by the photos an infrared thermal camera is totally different than a night vision camera for any and all applications. However, you typically see more night vision cameras in use because they are generally much less expensive than their thermal infrared cameras.